Wed, 16 Dec 2009 12:54:49 -0500
6843629: Make current hotspot build part of jdk5 control build
Summary: Source changes for older compilers plus makefile changes.
Reviewed-by: xlu
1 /*
2 * Copyright 2000-2008 Sun Microsystems, Inc. All Rights Reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
25 // This class provides the interface between a barrier implementation and
26 // the rest of the system.
28 class BarrierSet: public CHeapObj {
29 friend class VMStructs;
30 public:
31 enum Name {
32 ModRef,
33 CardTableModRef,
34 CardTableExtension,
35 G1SATBCT,
36 G1SATBCTLogging,
37 Other,
38 Uninit
39 };
41 protected:
42 int _max_covered_regions;
43 Name _kind;
45 public:
47 BarrierSet() { _kind = Uninit; }
48 // To get around prohibition on RTTI.
49 BarrierSet::Name kind() { return _kind; }
50 virtual bool is_a(BarrierSet::Name bsn) = 0;
52 // These operations indicate what kind of barriers the BarrierSet has.
53 virtual bool has_read_ref_barrier() = 0;
54 virtual bool has_read_prim_barrier() = 0;
55 virtual bool has_write_ref_barrier() = 0;
56 virtual bool has_write_ref_pre_barrier() = 0;
57 virtual bool has_write_prim_barrier() = 0;
59 // These functions indicate whether a particular access of the given
60 // kinds requires a barrier.
61 virtual bool read_ref_needs_barrier(void* field) = 0;
62 virtual bool read_prim_needs_barrier(HeapWord* field, size_t bytes) = 0;
63 virtual bool write_ref_needs_barrier(void* field, oop new_val) = 0;
64 virtual bool write_prim_needs_barrier(HeapWord* field, size_t bytes,
65 juint val1, juint val2) = 0;
67 // The first four operations provide a direct implementation of the
68 // barrier set. An interpreter loop, for example, could call these
69 // directly, as appropriate.
71 // Invoke the barrier, if any, necessary when reading the given ref field.
72 virtual void read_ref_field(void* field) = 0;
74 // Invoke the barrier, if any, necessary when reading the given primitive
75 // "field" of "bytes" bytes in "obj".
76 virtual void read_prim_field(HeapWord* field, size_t bytes) = 0;
78 // Invoke the barrier, if any, necessary when writing "new_val" into the
79 // ref field at "offset" in "obj".
80 // (For efficiency reasons, this operation is specialized for certain
81 // barrier types. Semantically, it should be thought of as a call to the
82 // virtual "_work" function below, which must implement the barrier.)
83 // First the pre-write versions...
84 template <class T> inline void write_ref_field_pre(T* field, oop new_val);
85 private:
86 // Keep this private so as to catch violations at build time.
87 virtual void write_ref_field_pre_work( void* field, oop new_val) { guarantee(false, "Not needed"); };
88 protected:
89 virtual void write_ref_field_pre_work( oop* field, oop new_val) {};
90 virtual void write_ref_field_pre_work(narrowOop* field, oop new_val) {};
91 public:
93 // ...then the post-write version.
94 inline void write_ref_field(void* field, oop new_val);
95 protected:
96 virtual void write_ref_field_work(void* field, oop new_val) = 0;
97 public:
99 // Invoke the barrier, if any, necessary when writing the "bytes"-byte
100 // value(s) "val1" (and "val2") into the primitive "field".
101 virtual void write_prim_field(HeapWord* field, size_t bytes,
102 juint val1, juint val2) = 0;
104 // Operations on arrays, or general regions (e.g., for "clone") may be
105 // optimized by some barriers.
107 // The first six operations tell whether such an optimization exists for
108 // the particular barrier.
109 virtual bool has_read_ref_array_opt() = 0;
110 virtual bool has_read_prim_array_opt() = 0;
111 virtual bool has_write_ref_array_pre_opt() { return true; }
112 virtual bool has_write_ref_array_opt() = 0;
113 virtual bool has_write_prim_array_opt() = 0;
115 virtual bool has_read_region_opt() = 0;
116 virtual bool has_write_region_opt() = 0;
118 // These operations should assert false unless the correponding operation
119 // above returns true. Otherwise, they should perform an appropriate
120 // barrier for an array whose elements are all in the given memory region.
121 virtual void read_ref_array(MemRegion mr) = 0;
122 virtual void read_prim_array(MemRegion mr) = 0;
124 virtual void write_ref_array_pre( oop* dst, int length) {}
125 virtual void write_ref_array_pre(narrowOop* dst, int length) {}
126 inline void write_ref_array(MemRegion mr);
128 // Static versions, suitable for calling from generated code.
129 static void static_write_ref_array_pre(HeapWord* start, size_t count);
130 static void static_write_ref_array_post(HeapWord* start, size_t count);
131 // Narrow oop versions of the above; count is # of array elements being written,
132 // starting with "start", which is HeapWord-aligned.
133 static void static_write_ref_array_pre_narrow(HeapWord* start, size_t count);
134 static void static_write_ref_array_post_narrow(HeapWord* start, size_t count);
136 protected:
137 virtual void write_ref_array_work(MemRegion mr) = 0;
138 public:
139 virtual void write_prim_array(MemRegion mr) = 0;
141 virtual void read_region(MemRegion mr) = 0;
143 // (For efficiency reasons, this operation is specialized for certain
144 // barrier types. Semantically, it should be thought of as a call to the
145 // virtual "_work" function below, which must implement the barrier.)
146 inline void write_region(MemRegion mr);
147 protected:
148 virtual void write_region_work(MemRegion mr) = 0;
149 public:
151 // Some barrier sets create tables whose elements correspond to parts of
152 // the heap; the CardTableModRefBS is an example. Such barrier sets will
153 // normally reserve space for such tables, and commit parts of the table
154 // "covering" parts of the heap that are committed. The constructor is
155 // passed the maximum number of independently committable subregions to
156 // be covered, and the "resize_covoered_region" function allows the
157 // sub-parts of the heap to inform the barrier set of changes of their
158 // sizes.
159 BarrierSet(int max_covered_regions) :
160 _max_covered_regions(max_covered_regions) {}
162 // Inform the BarrierSet that the the covered heap region that starts
163 // with "base" has been changed to have the given size (possibly from 0,
164 // for initialization.)
165 virtual void resize_covered_region(MemRegion new_region) = 0;
167 // If the barrier set imposes any alignment restrictions on boundaries
168 // within the heap, this function tells whether they are met.
169 virtual bool is_aligned(HeapWord* addr) = 0;
171 };